1. Field of the Invention
The present invention relates to a tape driving apparatus and a recording medium.
2. Description of the Related Art
A so-called tape streaming drive has been known as a driving apparatus which is capable of recording/reproducing digital data to/from a magnetic tape. The tape streaming drive is capable of having an enormous amount of recording capacity of several tens to several hundreds giga bytes for example, though it depends on the length of the tape in a tape cassette, i.e., a medium. Therefore, it is widely used for backing up data recorded in a medium such as a hard disk of a computer main body. It is also considered to be suitable for use in storing image data or the like whose data size is large.
Then, as the tape streaming drive as described above, there has been proposed one which is arranged so as to record/reproduce data by using a tape cassette of an 8 mm VTR as a recording medium and by adopting a helical scan scheme by means of recording and reproducing heads provided at certain positions of a rotary drum for example.
The tape streaming drive utilizing the tape cassette of 8 mm VTR as described above uses SCSI (Small Computer System Interface) for example as an input/output interface of recorded/reproduced data.
Then, in recording data, the data supplied from a host computer is inputted via the SCSI interface and the inputted data is compressed and encoded in a predetermined manner to be recorded in a magnetic tape of the tape cassette.
In reproducing data, the data in the magnetic tape is read, is decoded as necessary and is transmitted to the host computer via the SCSI interface.
By the way, the magnetic tape must be considerably long in order to have such a large capacity. Accordingly, recording/reproduction is carried out on the recording medium of such lengthy magnetic tape upon moving the magnetic tape to desirable position. However, it takes a considerable time depending on the relationship between the current position and the position where it is moved in case of the magnetic tape having such a large capacity because such move of the magnetic tape is carried out while recognizing the current position by reading certain management information recorded in the magnetic tape for example.
Then, it has been demanded to shorten the time in accessing to the desired position by quickly running the magnetic tape without reading the management information from the magnetic tape to move to the certain position.
In order to solve the above-mentioned problem, according to the invention, a tape driving apparatus comprises tape driving means for running a magnetic tape stored in a tape cassette when the tape cassette is loaded and for recording/reproducing information to/from the magnetic tape; memory driving means for implementing certain communicating processes to read/write management information from/to a memory when the tape cassette is provided with the memory for recording management information for managing the recording/reproducing operation to/from the magnetic tape; divisional information detecting means for detecting divisional information indicating divisional position unit of logical position information corresponding to positions of the magnetic tape physically and equally divided in the longitudinal direction thereof; target position setting means for setting position on the magnetic tape corresponding to one of the position information as target position; target running amount detecting means for detecting a target running amount based on the position information and divisional information from the current position of the magnetic tape to the target position; actual running amount detecting means for detecting an actual running amount from the point of time when the magnetic tape has started to run; and control means for running the magnetic tape without reading information on the magnetic tape until at least the actual running amount reaches to the target running amount while monitoring the actual running amount from the start of the run.
Further, in a recording medium comprising a tape cassette for storing a magnetic tape; and a memory, provided in the tape cassette, for storing management information for managing a recording/reproducing operation implemented to the magnetic tape, the memory stores logical position information corresponding to position physically and equally divided in the longitudinal direction of the magnetic tape and divisional unit information indicating divisional unit.
According to the invention, the tape driving apparatus is arranged so as to be able to detect the divisional information indicating the divisional position unit of logical position information corresponding to the positions of the magnetic tape physically and equally divided in the longitudinal direction thereof from the memory provided in the tape cassette. Thus, the target running amount from the current position to the target position may be calculated based on the divisional information and the tape running amount in the tape driving apparatus in carrying out High Speed Search by detecting the divisional information without reading information recorded in the magnetic tape.
The inventive recording medium can also supply the divisional information indicating the divisional position unit of the logical position information corresponding to the positions of the magnetic tape physically and equally divided in the longitudinal direction thereof to the tape driving apparatus in which the recording medium concerned is loaded.